CHARLOTTE, N.C. -- Some Carolina Panthers fans don't like the fact that their star quarterback, who is under concussion protocol and missed Monday night's game against Tampa Bay, was spotted in uptown before the game riding a scooter without a helmet.

The league's MVP last season, Newton suffered the concussion last Sunday after absorbing a helmet-to-helmet hit from Atlanta Falcons linebacker Deion Jones on a two-point conversion plunge.

The Carolina Panthers stumbled Monday night, losing a sloppy game to the Tampa Bay Buccaneers when rookie kicker Robert Aguayo’s 38-yard game-winning field goal provided the final 17-14 margin as time expired.

Now the Panthers are 1-4 and at the bottom of the NFC South.

Newton was not on the sidelines during the game.

"This loss is a tough pill to swallow because it was right there in front of us," Rivera said on Tuesday.

Backup quarterback Derek Anderson started in place of Newton and coughed up the ball three times, including a fourth-quarter interception from the Bucs' 1-yard line.

Carolina next faces the New Orleans Saints (1-3), desperately hoping to end its three-game skid. Whether Newton returns Sunday remains a mystery.